Door-alarm



(Model.)

(L A. SMITH.

DGOR ALARM.

Patented Aug. 8,1882

PTENJF CHARLES A. SMITH, OF Sl. LOUIS, MISSOURIJ DOOR -ALARM.

SPECIFICATION forming part of Letters Patent No. 262,490, dated August8, 1882.

Application filed June 9, 1882.

T0 all whom it may concern:

Be it known that I, CHARLES A. SMITH, of the city of St. Louis, in theState of Missouri, have in"ented a oertain new and nseful Im provementin Door-Alarms, of whieh the following is a full, olear, and exactdescription, referenoe being had to theacoompanyingdrawings, formingpart of this specifioation, and in whioh- Figure 1 is an end view; Fig.and Fig. 3 a front view.

My invention relates to an alarm operated on by a sliding bolt wbrked byeitl1er a knob or key.

A represents part of a door, and B the front wall of the frame, to Whiohis attaohed the keeper 0 for reeeiving the end of the slid ing bolt.

D is a plate seoured io the inside of the door, to whiol1 the bell andits parts are attaohed.

E is the sliding bolt, secured to the plate I) by straps F, whioh allowit to have ree end movement.

G is a transverse pin passing through the bolt, its ends protruding toengage with the front strap, F, to limit the forward movement of thebolt under the influenoe of a spring, H, which surrounds a post, I, andits ends bearing respeotively against the pin G and a stud, J. Thus thenormal position of the bolt is in engagement With the keeper C.

K is the bell or gong, oonneoted to the plate D by a post, L, and nut M.

N is a hammer, with a stem, 0, which surronnds a post, P.

Q is a short bar or pin passing transversely throngh the bolt E, andhaving pivoted to its 2, a side view,

lower end a swinging aam, R. When the bolt E is foroed back the lowercorner of this cam R comes against the upturned end of the stem Otheupper corner of the oan1 ooming against the lower edge of the bolt, asshown, so that the oam will not swing baokwardwhioh will foroe thehammer away from the edge of the bell. Tl1en When the end of the stemslips off the cam the hammer will be drawn back by a spring, S, andstrike the edge of the bell, giving an alarm. The backward movement ofthe hammer is limited by (Modol.)

| a pin, T. Then When the bolt is released it will move forward underthe influenoe of the spring H, the lower end of the oam R swing forward,and, passing over the end of the stem 0, the bell will agan be rung by ahammer, U, seoured to the back end of the bolt E. The bolt aan Deoperated either by the door-knob or bya key, and, if desired, the knobaan be looked and the bolt operated by thekey alone.

V is a tumbler, which is on and is turned by the shank of the knob V. Onthis tumbler are pins V V which, as the knob is turned, come in contactwith a pin or stad, E, on the top of the bolt E, moving the boltendwise, disengaging it from the keeper 0, and operating the hammer N.When the hammerN has been operated the bolt will have been disengagedfrom the keeper, but the pin V or V will not have left the pin E, sothat then is the proper time for the door to be opened; but one who isnot acenstomed to the devioeas a burglar, for instanoewould naturallyturn the knob until the pin V is disengaged from the pin E, and then thebolt will be moved i'orward and engaged with the keeper agan before thedoor aan be opened, operating the hammer U, whiel1 has the funotion ofgiving a second alarm When the door is opened and the knob released, orWhen the knob has been turned too farby one not accustomed to thedevice.

The knob aan he locked from turning by throwing over a plate, W, whiohwould engage with one of the pins V V. When the knob is tl1ns looked, orat any other time, the bolt may be operated by a key, X, whioh oomesagainst the upper end of the pin Q. The key-hole is plaoed forward ofthe pin Q, so that the key has a long hearing upon the p1n.

Electrcity may be used and the alarm turned into a jingle-bell by meansof an arm, Y, on the end of the bolt E, and an arm, Z, supported by apost, Z. 'lhus When the bolt is moved back the arms would oome together,conneoting theoironitandvibrating the arm U.

I claim as my invention-- 1. The combination of sliding bolt E, pin G,spring H, bar Q, swinging oam R, ham- IOO nier N O, spring S, be1l K,and suitable knob. made substantiaily as and for the pnrpose set 01 keyfor operating the bolt, as set orth. forth.

2. The combination of knob V, tumbler V,

with pins V W, sliding bolt E, secnred t0 GHARLEb bMITH' 5 the plate Fand h2wing pin 01 stnd E han1- Witnesses:

mer U, bar Q, cmn R, pin G, keeper 0, Spring SAML. KN1GHT,

H, hammer N 0, spring S, and bell K, 2111 GEO. II. KNIGH'I.

